Vapor electric device



u 5, 1932- M. SCHENKEL VAPOR ELECTRIC DEVICE Filed July 2, 1930 INVENTOR Morifz SceH/i Patented Aug. 16, 1932 Larmes fmzrzascnanxuulon iaimtrim.cimaterreni;naar ldrama-Aria ,AssIGNonf-.ro- :wrist: menousnamacmmcra ,MAnUmcrnmNe-cotrrmy, A,coascamel-:roi:,k or- PENN: e

i varon: EL-ecmmcpnylcne,

Application meauiy armo, serial No. 4e5,as,1,fana;sn GermaniaJulyaV leaaf My inventionrelates to vapor-electric devices and particularly to cathodes for such devices.

; In the operation of vapor electric appara- 5 tus, such as mercury-arc rectifers7 it has been found desirable to maintain the cathode spot in substantially a iixed position. Various expedients have been restored to maintain the Ycathode spot in a fixed position, among-which m Vhas been the use of a metallic pin projecting above the mercury, but this has been unsatisfactory because the heat of the cathode spot is sufficient to fuse most metals. Also, cath- 15 godes having very small mercury surfaces have cathodes, the mercury is not sufficient to carry away the heat generated at the cathode spot.

In addition to desiring a fixed cathode spot,

2 fait is also desirable to reduce, a'srmuch as pos- C sible, the vapor pressure in a vapor-electric device.

My invention contemplates the use of a fun- Y nel-shape'cathode shield having a perforationr figto maintain the cathode spot in a fixed position. Experiments have shown thatthe evaporation of mercury does not occur at the spot directly impinged by the rectifying arc but at a point that the cathode spot has just left mgpr, if the cathode spot is xed, Vfrom the regiony immediately around it. I believe thatthis lack of evaporation at the cathode spot is caused by the positive ions bombardina' the surface of the mercury at such spot andregjll-taining the evaporating mercury in a purely mechanical manner. As my funnel-shape shield maintains the cathode spot in a fixed position and, as the mercury vapor arises from the surface of the mercury around the H'eathode spot, I find it possible to deflect the rising mercury vapor into contact with a cooler placed immediately above the surface of the cathode, and, consequently, to condense the mercury vapor before it rises into themain iportion of the device. l

Other objectsand advantages will be apparent from thel following detailed description, taken in conjunction with the accomopanying drawing, in which,

' Figure l is a sectional elevation of a por-Y been used, but it has been found that, in such j tions. of.'*tliefsame:r-

plaeea inthe-@ahem Eansa '2. A 'funnel-- n i shapedshield'flbis placed immediately above? the"surf ac`e' of'theimercury; g'lhexspacingbje! i` l' tween .thei{botto'jn "of the* jshie'ld 10 andl the surface ofthemercury should; :prefe'ab'lbel 05 j ust sufficient? to "javoidI we ttirig! the shield when themercuryfis disturbedby' theifimpact/ of therectifyingarc.' The"small\.end opening Y l1 in theshield l() shouldfbof approxt" mately lthe same sizekasfthefmaximumsize 710W ingfll'iiiust-besuflicientlylarge,to pass the'tip Z5 i: I Y of eth efstartinggfanoole' 12. fTh'efoverall size vof my* funnel-"shapeshield "i should be suicient Y to cover the surface of the mercuryand' pre,-

the "gshield to an' exposed e mercuyi'sur-face., .0 I-Ifweve'r, the Ishield "must be 'se arated from er thedwvall .of the"tanl 'suiiciently to allofvvfcon-`lv derisedfriiercuryto back to thecathode f oder to prevent thearc striking any `portion oitf, I I j vAs the-evaporation z*from thecathode spot is comparativelysmall, when compared 'with l' thee evaporationtfrom aha-sufra@ f the?, 0

Vcatlrrciematerial! adjacent tolthefcathode spojt, r

it is'apparentthat the mercury vapor', rising' fromth ezcathoclefsurface", will 4`strike fa'gains't' f thefiunder-surfacie"ofthe'shieldand pass around orderrto reach' the main portion" of *the dev'ice l 'I takeadvantage'of this delietion ofthemercuryfvapor* to condense 'it 

